Wire feeder



Dec. 29, 1959 Original Filed Feb. 5,

C. H. K. SJQBOHM WIRE FEEDER 4 Sheets-Sheet 1 Dec. 29, 1959 c. H. K. SJOBOHM WIRE FEEDER 4 Sheets-Shee't 2 Original Filed Feb. 5, 1953 W -mmE NEE m -m=n KW m 1760672507: 61/67 H K 5J050H/W,

Dec. c H K SJOBOHM WIRE FEEDER Original Filed Feb. 5, 1953 4 Sheets-Sheet 3 //z 451 41a 0 W [50 H8. [1/ Mi #0 /Z6 /Z! O I I W f6 C. H. K. SJOBOHM Dec. 29, 1959 WIRE FEEDER 4 Sheets-Sheec 4 United WIRE FEEDER Curt H. K. Sjobohm, Worcester, Mass.

1 Claim. (Cl. 203150) This invention relates to a wire feeder, and especially to a wire feeder for use in coiled spring machines. This application is a division of my copending application Serial No. 335,302, filed February 5, 1953, now Patent No. 2,794,477, issued June 4, 1957. There are many types of wire feeders for use with machines for making coiled springs, but to my knowledge none of them can feed the spring forwardly a desired distance within close tolerances, either because of slippage in the grip on the wire or because of inaccuracy in the forwarding mechanism. Problems also arise because of the twisting of the wire being fed.

It is therefore an object of my invention to provide apparatus for feeding wire to a coil mechanism or the like with extreme accuracy.

This and other objects will be more apparent after reference to the following specification and attached drawings, in which:

Figure 1 is a top plan view of the machine showing the feeder of my invention incorporated therein and with parts removed for clarity;

Figure 2 is a side view of the machine of Figure 1;

Figure 3 is a front view of the machine of Figure 1;

Figure 4 is a sectional view taken on the line IVIV of Figure 2;

Figure 5 is an enlarged view of a detail of the machine;

Figure 6 is a sectional view taken on the line VI-VI of Figure l and showing the feeder of my invention;

Figure 7 is a view of a spring manufactured by the machine of my invention;

Figure 8 is a bottom plan view of the spring of Figure Figure 9 is a view taken on the line IXIX of Figure 2;

Figure 10 is an enlarged view showing the leading end of the spring wire being bent;

Figure 11 is an enlarged plan view showing the cutting and bending of the trailing end of the spring wire; and

Figure 12 is a perspective view of the wire feeder but showing the adjusting screw and parts actuated thereby on the side of the supporting arm opposite that shown in the other figures.

Referring more particularly to the drawings, the reference numeral 2 indicates a stand for supporting a wire drawing machine. A gear 4 is attached to a shaft 6 which is rotatably mounted on the stand 2. Power for rotating the gear 4 is provided from any suitable source. The face of the gear 4 is provided with diametrical guideways 8 for adjustment therein of a head 10'which carries a crank pin 12. One end of a connecting rod 14 is connected to the crank pin. The other end of the connecting rod 14 is pivotally connected to a slidable rack 16 which is guided in a horizontal path by means of suitable slideways on the supporting stand 2. The stroke of the sliding rack may be varied by adjusting the position of the head 10 in the guideways 8. The teeth of the rack 16 are in mesh with the teeth of a pinion 18 which atent is mounted on a vertical shaft A large gear 22 is rotatably mounted on the top of the shaft 20 and is driven by means of a clutch 24, such as the one shown in the patent to Thomas No, 1,935,137. A stop 26 is mounted on a periphery of the gear 22 and is adapted to contact a stop 28 which is pivotally mounted on a pin 30. The gear 22 is in mesh with an elongated pinion 32. The pinion 32 is secured to a vertical spindle 34 which is slidably journaled in bearings 36. A spring winding arbor 38 is attached to the bottom of the spindle 34. A vertical hole 40 is provided in the end of the spindle 34 adjacent its connection to the arbor 38.

The drive is provided with a squaring attachment and auxiliary lifting attachment *as described below. A member 42 is attached to the rack 16 for reciprocation there'- with. A stud or bolt 44 passes through member 42 and carries a U-shaped pitch shellf46 which is attached to the back of member 42. The pitch shell 46 is adapted to occupy various positions of angular adjustment with respect to member 42-so that the pitch of the spring coils can be varied. For this purpose the she'll 46 is pivoted about the bolt 44 and is held in adjusted position by means of a bolt 48 which passes through a slotted openf ing in the member 42. As best shown in Figures 4 and 5 the lower end of a grooved pitch cam 50 is received between the legs of the shell 46 and is pivotally connected to reciprocating bar 52 by means of a pin 54 received in the cam groove. The cam 50 is. pivotally fastened to the shell 46 by means of a screw 56 and is held in floating position by means of four springs 58. Additional holes '59 through the members 46 and 50 enable them to be rigidly fastened together when it is not desired to square the ends of the spring being formed. The reciprocating bar 52 has a pin 60 attached to its upper end. The pin 60 floats in slots 62 in a terminal fitting 64 attached to the end of pitch arm 66. Screws 68 are threaded into member 64 to provide stops for limiting the movement of pin 60 and bar 52. A spring 70 surrounds the reciprocating bar 52 with one end abutting against the lower part of fitting 64 and the other end bearing against a pin 72 mounted on the reciprocating bar 52. A collar 74 which serves as an abutment is attached to the reciprocating bar 52 and is provided with two openings, one at each end thereof, for receiving screws 78 which are mounted on a stationary guide 80 for reciprocating bar '52. Nuts 82 and 84 are provided on the screws 78 and serve as stops to limit movement of the collar 74. The pitch arm 66 is pivotally mounted intermediate its length on a pin 86. The other end of the arm 66 is pivotally connected to the spindle 34. link 88 has one end slidably attached to the arm 66 and the other end attached to the pivoted stop 28. A lever 90 attached to the pin 30 has its free end pivotallycon nected to a link or arm 92. The other end of link 92 extends toward the shaft 6 and has'a bifurcated block or yoke 94 attached thereto which surroundsthe shaft. A collar 95 is attached to the shaft 6 at one side of yoke 94. Cams 96 and 98 are fastened to the shaft 6 by means of set screws and are provided with high and low cylindrical surfaces. The purpose of cam 96 will appear later. The cam 98 is provided with a high portion which is adapted to engage a roller 100 mounted on a pin 102 attached to the yoke 94. The collar 95 and cam 98 cooperate to prevent the yoke 94 from moving'sidewise.

A bevel gear 106 is mounted on the free end of shaft 6 and is in mesh with a similar bevel gear 108 mounted on a rotatable shaft 110 which extends toward the front of the machine. A earn 112 is mounted on the shaft 110 intermediate its length. A bracket 114 for the wire feed ing mechanism is attached to the supporting frame 2 adjacent the cam 1'12. A stationary spacer block 116 is mounted on the bracket 114. The base 118 of the wire feed is slidably mounted on the block 116 for movement toward and away from the front of the machine. An extension 119 is bolted to the rear of base 118 and carries a rol1'120 which is adaptedto be contacted-by the cam 96. The extension 119 is slidable in a guide 121 mounted on stand 2. A pinion 122 is mounted on the base 118 and meshes with a stationary rack 124 and a movable rack 126 which is connected to a slide 128. The rack 124 is supported by brackets 129 which are mounted on stand 2. The cam 112 is adapted to contact a roller 130 which is connected to the free end of a pivotally mounted arm 132. An adjusting screw 134 is also mounted on the arm 132 and passes through a threaded opening in bracket 114. The screw 134 presses against a swinging bar 136 which is mounted for movement about a horizontal axis. The lower end of the bar 136 contacts the roller 135 at the end of the arm 137 of a earn 138 which is mounted on the slide 128 by means of a bolt 139. It will be noted that the adjusting screw 134 in Figure 12 is shown in a position between the shaft 6 and roller 130 and that the pivot for the arm 137 is on the end of the arm away from shaft 6, these arrangements being reversed from that shown in Figuresl and 6. However, the operation is the same in either case. This moves cam 138 against a gripping jaw 140, thus claming wire W against a stationary die 141. A spring 142 urges the jaw 140 against its cam 138. A plate 143 fastened to slide 128 holds the jaw 140 down against slide 128. The parts 142 and 143 are omitted from Figure 1 for reasons of clarity. When the slide 128 has traveled the desired distance the cam 112 is so positioned that both the lever 132 and the arm 137 can move outwardly by means of the pressure of a compression spring 144 having one end attached to the arm 137 and the other end to the slide 128, thus releasing the wire and allowing it to travel freely while the spring S is being wound on the arbor. A spring 144a attached to the frame 2 retracts the slide 118 when the low spot on cam 96 is reached. The wire W being fed passes through apparatus 145 which permits the wire to feed forwardly but prevents backward movement thereof. Apparatus suitable for this purpose is shown in the patent to D elihanty No. 1,026,567.

A gear 146 is mounted on the forward end of shaft 110 and is in mesh with a gear 148 mounted thereabove on a shaft 149. Two cams 150 and 151 are mounted on the shaft 149 and are adapted to be contacted by rollers 152, 153, 154 and 155 which are mounted on pivotally mounted levers 156, 157, 158 and 159, respectively. The levers 156 and 157 are connected by a spring 160 and levers 158 and 159 by a spring 161. The lever 156 has a slide 162 attached thereto which has its end shaped to form the male portion of the cutter and end forming mechanism. The lever 157 has a slide 163 attached thereto which is shaped to form the female portion of the cutter and end forming mechanism. The lever 159 has a slide 164 attached thereto by means of linkage 159a. The end of the slide 164 is provided with a bending tool 165. A vertical slot 166 is provided in the front face of a pipe cutter or cut off bushing 167 through which the wire W passes, and across the slotted end faceof which the shaped end of slide 162 moves in performing the, cutting operation. No novelty is claimed for this tool reciprocating mechanism since it is old as shown in the patent to Blount and Thomas No. 2,085,570 and not part of applicants invention. The lever 158 is not used except as an anchor for the spring 161 in the present invention, but may be used to operate a fourth slide whenthe machine is being used for other purposes.

The. operation of themachine is as follows:

Assume that the wire W is being fed to the coiler and that a spring S, such as shown in Figure 7 is being formed. One end 170 of the spring extends at right angles to the top coil of the spring and the other end 172 is bent radially outward from the bottom coil of the spring. The gear 4 continuously rotates shafts 6 and 110. After the end 172 of one formed spring is cut off the arbor 38 will have moved to its lowest position. The first step in the formation of the spring is the formation of the bend 170 in the end of the wire. This is accomplished by the slide 164 moving upwardly and the tool 165 bending the end of the wire upwardly into the slot 166 in the pipe cutter 167 as best shown in Figure 10. The cam 112 has reached a position where it moves the roller 130 inwardly, thus causing the screw 134 to bear against the swinging bar 136 which, in turn, moves the cam 138 against the jaw 140. This clamps the wire W between the jaw 146 and die 141 so that the wire cannot move longitudinally or rotate about its axis. Roller 120' is also in Contact with cam 96. In the meantime, cam 93 has contacted roller 100 which moves the arm 92 to rotate the lever 98 and cause link 88 to pull downwardly on pitch arm 66, thus moving the arbor 38 up out of the path of movement of the bent end 170 of the wire W. This movement is independent of the regular movement of the arm 66 caused by the pitch cam 50 and is made possible by the lost motion connection between the reciprocating bar 52 and pitch arm 66.- As the pitch arm 66 is pulled downwardly by link 88, the slots 62 permit the bottom stop 68 to move away from the pin 60. The movement is limited by the top stop 68 when one is provided. However, the top stop is not a necessity. With the arbor 38 up out of the way, the wire W is fed a short distance until it is positioned accurately under the hole 40. This is done by means ofcam 96 which moves slide 118 with gear 122 mounted thereon. The gear 122 will rotate in mesh with rack 124 and 126 and cause the rack 126 to move the slide 128 and the wire W accurately for a short distance. The continued rotation of gear 4 moves cams 96, 98 and 112 beyond their high spots so that the wire W is unclamped and the link 88 is free to move. The Wire W is prevented from moving rearwardly by the device 145, but is free to move forwardly. Also in the meantime, the stop 26 moves against pivoted stop 28 which at this portion of the spring forming cycle is stationary and in its lower position, thus positioning the hole 40 in accurate position to receive the bent end 170. After pressure on the link 88 is removed, the spring 70 forces pitch arm 66 upwardly until the lower stop 68 contacts pin 60. This moves the spindle 34 downwardly and positions the wire end 171) in the hole 40. The gear 22 then rotates in a counterclockwisedirection as seen in Figure 1 to rotate the arbor 38. At the same time the arbor 38 is moved upwardly by the pitch lever 52. The combined rotation and upward movement of the arbor 38 pulls wire from the supply coil and forms the convolutions of the spring S.

slides 162 and 163 to'move toward each other.

The coils at either or both ends may be made square; that is, at right angles to the axis of the spring in the following manner: Adjacent the end of the stroke of the rack 16 with the pitch shell 46 mounted thereon, the collar 74 will strike nuts 82 or 84, depending upon the direction of travel, and stop the movement of reciproeating bar 52 While the arbor 38 is rotating and forming either the first or last coil of the spring S. Thus, there will be no feed of the arbor for these coils and they will be square. This is made possible by the use of the pivoted pitch cam 50 and springs 58 which permit movement of the cam 50 with respect to the pitch shell 46. If squaring of only one end of the spring is desired, the springs above or below the cam 56 and one pair of stop nuts 82 or 84 may be omitted depending upon the end of the spring which i being squared.

When all the coils are formed in the spring, the cam 150, rollers 152 and 153, and spring will move the levers 156 and 157 toward each other, thus causing the The shaped end of slide 162 moves across the end face of cut off bushing 162, thus cutting the wire W to the desired length and forming the end 172 onthe spring as shown in Figure 11. The machine is then ready to form another spring.

While one embodiment of my invention has been shown and described it will be apparent that various modifications and adaptations may be made without departing from the scope of the following claim.

I claim:

A wire feeder comprising a bracket, 21 member slidable on said bracket axially of said wire, a roller attached to the entry end of said member, a rotary cam mounted'adjacent said roller for moving said member in the direction of feed, a spring having one end stationary and the other end attached to said member for urging said member toward said cam, a pinion mounted on said member with its axis vertical, a slide mounted on said member for movement with respect thereto axially of said wire, a rack on said slide in mesh with said pinion, a stationary rack in mesh with said pinion, a die mounted on said slide for movement therewith, a gripping jaw mounted on said slide for movement transversely of said wire toward and away from said die, a cam pivotally mounted on said slide for movement in a horizontal plane and adapted to contact said jaw, an actuating arm connected to said last named cam, a roller on the end. of said arm, a swinging bar mounted on a horizontal axis and having its lower end in contact with said last named roller, a rotary cam mounted adjacent said swinging bar, means actuated by said last named cam for moving said swinging bar into contact with said last named roller, a spring urging said slidable jaw into contact with its cam, and a spring urging said arm away from said die.

References Cited in the file of this patent UNITED STATES PATENTS 737,340 Campbell Aug. 25, 1903 1,828,413 Holmes Oct. 20, 1931 2,163,019 Blount et al. June 20, 1939 

